Crank case ventilator



April 1934- w. s. COCHRANE 1,954,198

CRANK CASE VENTILATOR Filed Aug. 6, 1926 3 "me/M01,

Wm TE}? 5. COCH/F/INE Patented Apr. 10, 1934 UNITED STATES PATENT OFFICE CRANK CASE VENTILATOR ration of Delaware Application August 6, 1926, Serial No. 127,598

4 Claims.

This invention relates to crank case ventilation and is illustrated as embodied in an internal combustion engine designed for use in motor vehicles.

It has been found that the lubricant in the crank case of an internal combustion engine is diluted by the gases from the explosion chamber leaking past the piston or valves and that the vapors are condensed within the crank case which dilute the lubricant, due to the dead air in the crank case chamber.

It is therefore an object of this invention to remove the gases and vapor from the crank case by causing a circulation of air therethru.

Another object of the invention is to remove the gases and vapor from the crank case by suction of the intake manifold through the carburetor and air cleaner. If too much suction is applied to the crank case, such as under open throttle conditions the lubricant is drawn from the crank case which is objectionable and a further object of the invention is to control the amount of suction from the crank case through the control for the speed of the engine.

These and other objects will more fully appear from the following description taken in connection with theaccompanying drawing, in which:

Fig. 1 is a side elevation of an engine showing an adaptation of my invention.

Fig. 2 is a sectional view on line 2-2 of Fig. 1.

Referring to the drawing, an internal combustion engine 10 is shown provided with an inlet manifold 12 and carburetor 14. An air cleaner 16 is attached tothe carburetor to clean the air admitted to the latter through the passage 18. The air cleaner shown is of the centrifugal type and the air is admitted through openings 20 at the top thereof.

At one side of the air cleaner an opening 22 has been provided to receive one end of a conduit 24. The opposite end of the conduit 24 is received by a boss 26 in the valve tappet cover 28. The valve tappet chamber 30 is open to the crank case 32 as at 34 and a breather or oil filler is shown at 36.

When the motor is started, it will be understood that the suction in the intake manifold will draw air through the carburetor and air cleaner 16, and that a suction will be applied through the conduit 24, chamber 30, opening 34 and crank case 32; air being admitted through the breather 36.

To avoid too great a suction in the crank case, under open throttle conditions, a valve 38 has been provided in the conduit 24, regulated by the throttle control. The control 40 is attached to a crank arm 42 operating the valve 44 in the carburetor and at the opposite side of the carburetor is another crank arm 46 which is connected to an arm 48 thru the connection 50. Attached to the arm 48 is an adjustable link 52 connected to a crank arm 54 which operates the valve 38. By such an arrangement, when the throttle valve is opened the passage in the conduit 24 is restricted, thus preventing too much suction and consequently no lubricant is carried with the vapors through the conduit 24.

While I have described what I deem to be the preferred form of my device, it is not my intention to limit its scope other than by the terms of the appended claims.

What I claim is:

1. The combination with an internal combustion engine including a carburetor, an air intake connected with said carburetor having openings from the engine crank case and from the outside and means operable by an increase in the speed of the engine for progressively restricting the effective size of the opening from the crank case.

2. The combination with an internal combustion engine having a throttle controlled intake, of a connection establishing communication between the crank case and intake, and means whereby the capacity of said connection is caused to vary inversely with the opening and closing of the throttle.

3. In combination with an internal combustion engine including a throttle controlled intake, an opening in the intake leading to the engine crank case, and element movable to vary the effective size of said opening, and means operated by opening and closing of the throttle for moving said element.

4. The combination of an internal combustion engine having a crank case and a throttle valve, said crank case being provided with an inlet passage and an outlet passage, means for causing a stream of air to be drawn into said crank case through the inlet passage and discharged through said outlet passage. a valve in one of said passages, and means connecting said valve for causing the second named valve to close as the throttle valve is opened.

WALTER S. COCHRANE. 

